Power-brake mechanism



Nov. 5, 1929. A. l.. ROBERTS POWER BRAKE MECHANISM Filed Nov. 21, 1927 5 Sheets-Sheet i lI H' Timm-"11F n,

Filed N Ov. 2l, 1927 3 Sheets-Sheet Afm.

Nov. 5,' 1929.

A. l.. ROBERTS POWER BRAKE MECHANISM Filed Nov. 21, 1927 3 Sheets-Sheet Patented Nov. 5, 1929 UNITED STATES .ALVIN L., ROBERTS, OF PH'JLADELPHIA, PENNSYLVANIA i POVER-BBAKE MECHANISM Application. filed November 21, 1927'.

My invention relates to improvements in brake mechanism in which power from a rotating shaft of a motor vehicle is utilized in applying ythe brakes,-this application embodying improvements upon that which is disclosed in application for patent filed by me on the 15th day of April, 1927, and designated by Serial No. 133,998.

One object of my present invention is to provide a positive and reliable mechanism to apply a. braking force to a motor vehicle, in which power may be taken from any desired rotating shafton the vehicle, regardless of the direction of rotation of such shaft, or

Y whether the vehicle is running forwardly or backwardly, and thus relieve the operator from the severe muscular effort required to control the movement of a vehicle with the use of brakes applied with power acquired solely from the operation of a foot lever.

lith this and other objects in view, the invention consists in certain novel features of construction and combinations of parts as hereinafter set forth and pointed out in the claims.

In the accompanying drawings;

Figure 1 .is a'view partly in side elevation and partly in section, illustrating an application of my improvements;

Figure 2 is a fragmentary plan view of a portion of the structure shown in Figure 1;

Figure 3 is a view in section on the line 3--3 of Figure 6;

Figure dis an edge view showing trunnion brackets;

Figure 5 is a separate view showing the lever 70 on t1 shaft 46;

the

Figure (3 is a view partly in section and partly in side elevation, illustrating the means for in'iparting a pulling action to the brake rod when the brake-controlling mechanism is actuated by power derived from a sha-ft running in one direction or the other;

Figure 7 is a sectional view through the enclosed mechanism including the gearing and clutch devices, and

Figures 8, 9, 10, 11 and 12 are views of details.

lhile my improvements are applicable to motor vehicles of various types, still they Serial No. 234,761.`

are intended for use busses and trucks. i

A casing 1 made in upper and lower sections secured together', is supported by angle beams 2 2 forming part of the chassis and 55 said casing is preferably located in the space between one of the side members of the chasprovide some reduction of speed for said shaft, and a speed of rotation to be obtained satisfactory for the operation of the brake.

A central shaft 5 extends through the casing 1 and is mounted, through the medium of `bushings 6, 7, in the end portions thereof. One end of the shaft 5 may have a collar 8 secured thereto and made. to overlap the outer end of the bushing (3` and also the enlargement of the casing in which said bushing is located. The other end of the shaft 5 is provided with a threaded yshank which receives a nut 9 between which and the outer end of the bushing 7, a washer 10 may be located'. The bushing 7 is of such length relatively to the length of the enlargement on the casing in which it is mounted, that said bushing is permitted to have a slight endwise movement,the opening 11 in the bushing into which the pin or key 12 enters lbeing somewhat elongated to facilitate such endwise movement of the bushing.

' A cam member 13 is mounted on the shaft 5 and abuts against the inner flanged end of the bushing 7. To prevent `rot-ation of the' member 13, it may be provided with spaced klugs 111 which straddle a lug 15 in the casing 1.

The cam member 13 is made with an annular series of cam faces 17 which cooperate with similar cam faces 18 ou a cam meinparticularly 'on heavy ber 19,-the latter being provided with a spur gear segment 2O for a purpose hereinafter explained. rlhe member 19 is rotatably mounted on the hub 21 of a clutch disk 22 having an annular flange 23, which disk is movable upon the shaft longitudinally of the latter but which is prevented from rotation by the engagement of lugs 24 thereon with notched enlargements 25 within the casing. A bushing 26 is fitted on the shaft 5 between a flange 2'? thereon and the disk 22 and has a flange 28 abutting said fia-nge 2?'. T he hub 29 of a second clutch disk 30 is mounted on the bushing 26, and near its edge, said disk 30 is provided with an internal gear 31, and in the plane of this gear, a pinion 32 is keyed to the shaft 5 adjacent to the flange 2.7 on said shaft. Disposed between and meshing with the pinion 32 and the internal gear 81 are planetary pinions 33 mounted on pins or studs 34 carried by a frame 35 rotatably mounted on the hub 36 of a worm gear 37 keyed on the shaft 5. The worm gear receives motion from a worm 38 located within the casing and carried by the shaft 3.

Between the clutch disks 22 and 36 two series of clutch plates 39-40 are disposed, the plates S9 Vbeing carried by the flanged clutch disk 22 and the plates '40 (which alternate with the plates 39) being carried by the hub of the clutch disk 36. Normally the clutch plates of one series are slightly spaced from the clutch plates of the other series, and this is accomplished by the act-ion of springs 41 which are seated in pockets 42 on the casing and bear against the free edge of the flange 23 ofthe clutch disk 22, as clearly shown in Fig. 7.

The casing is formed, at its front and rear respectively, with extensions 43 and 44 and rock shafts 45 and 46 are mounted in the respective extensions. A gear sector 47 is carried by the shaft 45 within. the casing and meshes with the segmental gear 2O on tne cam member 19, while'a sector 48 on the shaft 46 within the casing enlargement 44 meshes with a rack 49 on the frame 35.

L A crank arm 50 is secure i to and depends from the outer end of the shaft 45 and has attached to it, one end of a rod 51, the other end of which latter is to be connected with a pedal or hand lever, with the use of which the operator may control the operation of the brake applying mechanism. The shaft 46 is connected, through the medium of instrumentalities presently described, with brake rod 52, the latter being connected with the brake rigging indicated generally at 53 in Figure 1. A spring 54 connected at one end with the framework of the car and at the other end with the brake rod 52 serves 'to retain the brakes in normal released position and a spring 55 connected at one end with the framework and at the other end with the rod 5l serves o retain the parts IOCL turned in one direction or the other. Said connections include a lever 59 with the central portion of which the brake rod 52 is connected. rlhe respective ends of the lever 59 are bifurcated and velongated as at 60-60 and from the inner ends of these portions of the lever 59. trunnions 61 project laterally at each side of the leverand at respective ends thereof, said trunnions eing adapted to engage bearing fianges 62 on the inner faces of n bracket 56 at the top and bottom portions thereof. Each bearing flange 62 is made hook-shaped at its rear end as at 63 to receive the trunnions 6l, and it will be evident that the lever 59 may turn on either the upper or the lower trunnions and in either case impart a pulling action to the brake rod 52 to effect the setting of the brakes. ln order that proper spacing of the brackets 50 shall b insured and maintained, said brackets may be spaced by a sleeve 64 and a bolt 65 passed through said sleeve and through holes such as indicated at 66 Figure 10 in said brackets, said bolt being provided at one end with a head and at the other end with a nut. Two arms 6T are mounted loosely on the projecting end portion of the shaft 46, one of said arms projecting upwardly and rearwardly and the other arm prog'ecting downwardly and rearwardly. and said arms are connected respectively, by means of adjustable connections 66, with the upper and lower ends of the lever 59 as at 69 in the rear portions of l tne elongated. bifurcated upper and lower ends of said lever. A lever 70 is keyed to the shaft 46 and engages the arms 67, 67 respectively above and below the mountings of said arms. lt is evident that when the shaft 46 is turned in one direction. the lever 70, engaging the upper arm 67, will move the saine forwardly, causing the lever 59 to turn on its lower fulcrums and impart a pull to the brake rod, and that when the shaft 46 is turned in the reverse direction, the lever 70, .engaging the lower arm 67, will cause this lower arm to be moved forwardly and cause the lever 59 to turn on its upper fulcrums and impart a pulling action to the brake rod.

Since the shaft 8 is directly connected with some rotating shaft on the vehicle, it will always be in rotation in one direction or the other when driven, for instance, by the pio peller shaft which is subject to rotation in either direction when the vehicle is in motion, either forward or backward. Rotation of the shaft 3 Will cause rotation of the Worm gearing B7-3Q, the center shaft 5 and the pinions Since the spring 54C holds the brakes in. ofi' position and the rod has a positive connection through the devices above `described and through the shaft 4G, sector @L9 and rack 48 with the frame 35, said frame will be heid normally stationaryv as .long as the b 'akes'are Wlhile the frame 35 is normallyy held sationary 'as above described, the meshing of the planetary pinions 33 with the internal gear 31 on the clutch disk 30, will cause the latter to rotate and carry with it, the clutch plates 40. rllhe clutch disk pressed back by the springs di and the cam member 1f) carried on the hub of said disk will likewise be forced back into intimate mesh with the cam member 13. its the clutch plates 3Q-10 are normallj,7 held slightly sep"- rrated by the action of the springs l,il as previously explained, the disk 3() and the clutch plates 40 as well as the igfiternal gear 8l carried by said disk are normallyv free to .rotate Without frictienal Contact of the sets 39 and LiO of friction plates.

Willen pressure is applied to the foot lever with which the 'od 51 is connected, said rod will be drawn forwardly. This will canse partial rotation of the gear sector' 47 and motion will be imparted, through the gear segment 2O to die cam member 19. Rotation of the cam member 10u/ill cause separation ofthe ktive Cain members 19 and i3 by the coaction of the opposing cam faces, thereby noving` the clutch disk 22 and the clutch plates carried thereby, again. t the resistance of the springs Lil and bringing the clutch plates 39 into rrictional cooperation -with the clutch plates d() carried by the clutch disk 30. The degree of pressure of the clutch pla es ft? against the clutch plates 4:0, will depend upon and be proportional to the ame-f,

fo di increment of a id pre. sure exerted on the foot lever With which the rod 5l 1s connected.

lt will be reiner tiered that 'the frame 35 is normally held f tienarfv by the action of retractinfi spring' 5i and that the internal gear Si. is rol because it is being); driven by reason direct connection with the source of pover., Pressure of theplates fifi-#LO of the friction clutch cannot stop rotation said internal ear and 'the ciutch dis 30 eifen therecf, but any',Y pressure 'ction clutch to bringt the al coeperatien, will i; .n of a t1 ninev effort .rame 35. Continued move- 1 iever will canse such torque o the point Where it Will ovef l rotractintr spri i 'f nic F35 will immediiwely begin to move in one direction or the other, de-

pending onthe direction of rotation of the driving shaft 3, this movement being imparted directly to the rack 49 and thence to the sector l? and shaft 16, and continuing until the brake shoes are in contact with the brake drums. The movements of all the parts, including' the foot lever, then cease. (,lontinue l pressure on the foot lever may then be increased and the mechanism caused to bring about effective braking' action, and the application of the brakes will continue as long); as pressure on the foot lever .is maintiined. of pressure from the foot lever will result in immediate release of the brake and the retracting springs 54 and 55 will return the parts to their normal posi tions.

Having fully described my invention what l clain as ind desire to secure by Letters- Reiease nervt atent, is :-y

i. ln power brake mechanism, the combination with a brake rod, a rock shaft, power operated nie-,ans for turni.1n seid shaft, and n ..isciileiij,v operabie in for controlling said power operated means, of a lever keyed t saidrfw17 shaft, ogpositelj/ disposed pivotally suppe. Vd arms engagedbj' said lever, a levernioru d for pivotal support at each of ends, connections between said pivotally supported arms and resg'iective entre ef said rast mentioned lever, and a Vconnection interi mediate the ends of the latter and the brake rod.

2. .in a poirier b `ake .mecbanisnn the combination With roc r shaft, power operated in ans for turningl roeishaft, and musorderly operable n'ieans for centrfilling` the newer operated means, of fixed su ipcrts havi i yfrloiver elcngatedbeari ut re pecti're ondst a power brake mechan; n with a rock shaft, perfer operated turning,` sain rock she/ f 1 muscui contri; iingthepover d means, cf fixed spaced brackets each with upper :31d lower elongretct ans, a le entering between said te 'ally jirojecting trunniens at ref e 'd lever avid cooperable l ioiver el binat-i meer,

.. interf 7 L `lVV lever, ippositeiy disnortien' of )osed pivoted arms, connections between the itil) respective pivoted arms and respective end portions of said lever, and a member fined to said rock shaft and cooperable with the pivoted arms to move one or the other according to the direction of rotation of the rock shaft and cause rocking of said lever on the trunnion bearings at one end or the other of said lever.

et. ln a power brake mechanism the combination with a rock shaft, power operated means for turning said rock shaft, and muscularlf: operable in s for tonigoiling yowef.` operated means, of fixed supporting means, a lever having pivotal mounting at each of its ends on said supporting means, a brake rod connected with an intermediate portion of said lever, oppositely disposed arms loosely mounted upon said rock shaft, connections between the respective arms and respective ends of said lever, and a lever fined to the rock shaft and engaging each of said arms.

5. ln a power brake mechanism, the combination of a rock shaft, brake applying means connected with said rock shaft, a frame mounted to oscillate, gearing between said rock shaft and said frame, planetary gears carried by said frame, power driven means for rotating said planetary gears, two clutch disks, a gear carried by one of said clutch disks and meshing with said planetary gears, a set of clutch plates carried by each of the clutch disks, springs engaging one of said clutch disks and causing the clutch plates carried thereby to be maintained normally out of frictional cooperation with the clutch plates carried by the other clutch disk, and muscularly controlled means for moving one of said clutch disks relatively to the other against the resistance of said springs to bring the respective sets of clutch plates into fric- 'ional cooperation and cause turning of said i une to impart turning movement to said rock shaft and actuate the brake applying means connected with the same.

ln a power brake mechanism, the combination of a rock shaft, brake applying means connected with said rock shaft, a frame mounted to oscillate, gearing between said rock shaft antL said frame, planetary gears carried by said frame, power driven means for rotating said planetary gears, two clutch disks, a gear carried by one of said clutch .s and meshing with said planetary gears,

a set of clutch plates carried by each of the clutch disks, springs engaging one of said cli ch disks and causing the clutch plates car- -d thereby to be maintained normally out of frictional cooperation with the clutch plates carried by the other clutch disk, muscularly controlled means for moving one of said clutch disks relatively to the other against the resis ance of said springs to bring the respective sets of clutch plates into frictional cooperation and cause turning of said frame to impart turning movement to said rock shaft and .aetuate the brake applying means connected with the saine, and spring means connected with the brake applying means and operable to retain the brakes normally in Gd position and also to normally prevent the turning of said rock shaft and the oscillatory frame geared therewith.

7. ln power brake mechanism, the combination with a casing, a rock shaft, brake applying means connected with said rock shaft, an oscillatory frame, gearing between said oscillatory frame and said rock shaft, planetary gears carried by said oscillatory frame, power means for rotating said planetary gears, two clutch disks, one being movable relatively to the other, means cooperable with the casing to 'prevent said movable clutch lisk from turning, a gear carried by the other utch disk and meshing with said planetary a set of clutch plates carried by each of Y'aid clutch disks, springs engaging the casing and said movable clutch disk and acting :ri .f to retain the sets of clutch plates out ional cooperation, and muscularly rolled cam devices for moving the movdisk to bring the sets of clutch plates into frictional cooperation.

8. ln a power brake mechanism, the comiin ion of a support, a. lever mounted to rock -iout either of its ends on the support, a uralte rod connected to said lever between the ends thereof, oppositely extending arms mounted to rock about a common center, connections between the free ends of said arms and corresponding ends of the lever, powerdriven means for `rocking said arms, and muscularly operated means for controlling said power-driven means. i

9. ln a power brake mechanism, the combination of a support, a lever mounted to rock about either of its ends on the support, a brake rod connected to an intermediate point ofthe lever, a rock shaft, connections between opposite sides of the rock shaft and the ends of the lever, cooperating clutch elements, planetary gearing connecting one clutch element with the rock shaft, power-driven means for actuating said gearing, means holding the clutch elements normally out of engagement whereby the rock shaft will be inactive and the clutch element geared thereto will rotate, means to hold the other clutch element against rotation, and muscularly operable means for effecting engagement 0f the clutch elements whereby bot-h clutch elements will be held stationary and the rock shaft will be actuated to apply the brakes.

ln testimony `whereof, l have signed this specification.

ALVlll L. ROBERTS. 

